红宝石lambda上下文 [英] ruby lambda context

问题描述

让我们在最顶层定义以下红宝石定义

Lets say I have the following ruby definition at the topmost level

callable = lambda {"#{hi}"}

，并假设稍后我创建一个名为temp的对象，该对象具有一个名为hi的方法.现在我想做的是在temp的上下文中调用callable.我已经尝试过了

and suppose that later on I create an object called temp that has a method called hi. Now what I would like to do is call callable within the context of temp. I have tried doing

temp.instance_eval do callable.call end

但是这给了我错误"NameError: undefined local variable or method 'hi' for main:Object".我想知道是否有任何方法可以将callable的上下文重新绑定到temp，这样我就不会收到错误消息?我知道我可以在main:Object上定义method_missing并将所有方法调用重新路由到temp，但这似乎实在太大了，无法完成我想要的事情.

but this gives me the error "NameError: undefined local variable or method 'hi' for main:Object". I would like to know if there is any way to rebind the context of callable to temp so that I don't get an error message? I know that I could define method_missing on main:Object and reroute all method calls to temp but this seems like way too big of a hack to accomplish what I want.

推荐答案

您正在寻找的代码是

temp.instance_eval(&callable)

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